Drilling bit



F. CLARK June 2%, 19339 DRILLING BIT Filed Sept. 7, 1932 ATTORNEY Patented June 20,, 1933 PATENT orrica FRED CLARK, F GLADEWA'I'EB,

DRILLING BIT Application fled. September 7, 1932. Serial No. esaou.

The invention relates to a drilling bit and more particularly to a four-wa shearlng blade straight hole bit for use in o' well drill in r1 he iirimary object of the invention is the provision of a bit of this character, wherein there is arranged a central novelly formed pilot blade with two cutting edges, while about the same are shear blades, these being of peculiar formation so as to cause a reaming action and shear or cut the soil, rock and other matter in contradistinction to a dragging operation thereon and also to force the cut material or matter toward the center of the hole as the blades shear or cut during each revolution of the bit.

Another object of the invention is the pro 3 v vision of a bit of this character wherein the same is adaptable for use with rotary drilling rigs in digging oil and as wells, water Wells and other wells and t e itch of the shear blades being such as to de ect a Water jet onto the points of said blades, the water being fed through the bit directly in front 2 of the blades thereof, the bit being of novel construction to assure a positive shearing or cutting action and a straight line boring efiect without liabilit of dragging of the cut matter with the resu t that the cuttings will a 3 be thoroughl broken up and the water feed through the it dissolving such cuttings and washing the same away while the bit is in operation,

A further object of the invention is the 5 provision of a bit of this character which is extremely simple in construction, thoroughly efiicacious and reliable in the operation thereof, strong, durable, and inexpensive to manufacture. i

"With these and other objects in View, the invention consists in the features of construction, combination and arrangement of parts as will be hereinafter more fully described in detail, illustrated in the accompanying drawing, which discloses the preferred embodiment of the invention, and pointed out in the claims hereunto appended.

In the accompanying drawing: Figure 1 is a bottom plan view of a bit constructed in accordance with the invention.

Figure'2 is a side elevation thereof.

Figure 3 is a front view of the bit.

Figure 4 is a sectional view on the line H of Figure 1 looking in the direction of the arrows. x

Similar reference characters indicate corresponding parts throughout the several 1 views in the drawin Referring to the drawing in detail, the bit constituting the present invention comprises a body 5 in the form of a circular stock having centrally'thereof a recess 6 which opens through the nipple end 7 of the same and this .s nipple end is in this instance internall threaded at 8 for the attachment of the stoc .5 to a drill shank or rod, it being undersood of course that the said stock may be otherwise attached if found desirable.

, The stock 5 has formed at its outer or working end the diametrically opposed tangentially arranged outeroutting blades 9, these being extended beyond the outer surface of the stock longitudinally thereof for a major portion of its length while formed at substantially right angles to these blades 9 are the radially disposed outwardly extending follower blades 10, these having the bev-' eled side shear or cutting edges-11 and likewise the blades 9 have the beveled shear or cutting edges 12, thus by this disposition of these blades 9 and 10 the same present a four bladed shear cutter or bit. The blades 9 protrude beyond the outer end of the stock 5 and are formed with beveled reversely angled edged tips 13, while the blades 10 are terminated at their outer ends inwardly with respect to the tips 13 and have their outer surfaces rounded at 14 for the tapered formation thereof in the direction of the ti s l3.' It will be apparent that the blades 12 he tangentially to the stool; 5 while the blades 10 are disposed radially with respect to said stock and these blades 10 on rotation of the stock follow the blades 9 for shear cutting action corresponding to the said blades 9.

Arranged diametrically opposite each other and at the outer portion of the stock 5 midway between the blades 9 is a pair of shear blades 15, these at their outer side edges terminating 'i'as with the outer surface of mo the stock and the same are disposed at a tangent to the axis of the stock and at an angle to the blades 9, the ti s 16 of these blades 15 having reversely ang ed edges 17 and func- 5 tion in the working of the bit for reaming action.

At the outer end of the stock 5 centrally thereof is a double bevel edged pilot blade 18, the beveled edges 19 being offset in arallel relation to each other of the pilot bla e 18.

Leading from the recess 6 in the stock immediately forwardly of the blades 9, 15 and 18 are water passages 20 which serve to render a water jet onto these blades for the cleaning thereof of the cuttings and also for the dissolving of the latter and the washing away of the matter or material when the bit is active in the drillin of a well either oil, gas or water. The'pitc or disposition of the blades 9 and 15 serves to force the cutting to the center of said bit and the said blades 15 by the set or pitch thereof are at the proper angle for shearing or cutting the material from the side and bottom of the bore rather than gouging or dragging action thereon. These blades 15 are placed one on each side of the pilot blade 18 and at an angle of approximately twenty degrees to thirty degrees rom the parallel with the inner edges slightly shorter thanthe outer or shearing edges thereof, causing the tips to slope or slant inwardly at an angle of approximately twenty-two degrees with the result that the outer blades 9 and cut or shear in advance of'the same with a tendency to hold the bit to a perpendicular downward course and preventing the hole from angling off at a tangent.

It will be obvious that the passages 20 next to the blades 9 are larger than those next to the pilot blade 18 and are so dis osed or pitched as to direct the water jet to t e points and cutting edges of these blades. It also "will be noted that the water pasages 20 are located in front of the shearblades and that said shear blades 9, 11 and 15, as well as the pilot blade 18, are thinner at the tips or points and edges than elsewhere and thicker almost immediately in the direction of the stock 5 of the bit.

The blades 9 are set at an angle of approximately fifteen degrees to twenty degrees bisecting a line. drawn parallel with the pilot blade and these are the longer of the remainingnblades of the bit. e bit in its operation is designed to shear the material away rather than gouge or drag it and to mantain or keep a straighter new pendicular hole throu hout ope tie The pilot blade bight 2i therei' twist caus' or thrus siderably and thus tending to again hold the bit in a straight downward line, the water passages 20 next to this blade being in front of the cutting edges 19 and so placed and pitched as to direct the water jet to the cutting edges and points of the pilot blade.

What is claimed is:

1. A bit of the character described comprising a body forming a circular stock having a central recess and a nipple end through which the recess opens, threads internally of the nipple for attachment of a drill shank therewith, diametrically opposed tangentially arranged outer cutting blades on said stock and extended beyond the outer face lon 'tudinally thereof for a major portion 0 its length, radiall disposed outwardly extendin follower b ades on the stock at substantia ly right angles to the first named blades and having beveled shear edges, said first named blades having beveled shear edges, beveled reversely angled edged tips formed on the first named blades and protruded beyond'the ends of the stock opposite the nipple, the second named blades being terminated inwardly with respect to the tips and having their outer surface's rounded and tapering in the direction of the tips, a pair of shear blades located on the stock midway between the first named blades and terminating flush with the outer face of said stock and disposed at a tangent to the axis thereof, and a pilot blade centrall von theouter end of the stock and havin ouble beveled edges, one beveled edge of t e latter being offset in parallel relation to the other.

2. A bit of the character described comprising a body forming a circular stock havingla central recess and a nipple end through w 'ch the recess opens, threads internally of the nipple for attachment of a drill shank therewith, diametrically opposed tangentially arranged outer cutting blades on said stock and extended beyond the outer face longitudinally thereof for a major portion of its length radiall disposed outwardly extending follower b ades on the stock at substantially right angles to the first named blades and having beveled shear edges, said first named blades having beveled shear edges, beveled reversely angled edged tips formed on the first named blades and protruded beyond the ends of the stock opposite the nipple, the second named blades being terminated inwardly with respect to the tips and having their outer surfaces rounded and taporing in the direction of the tips, a pair of shear blades iocated on the stool; midway between first blades and te the sec :2: a

havin water passages leading from the recess t erein to poiuts-inwardly with respect to the first and second named blades and opening through the outer end of the'stock. 5 3. A bit of the character described comprising a body formin a circular stock having a central recess an a nipple end through which the recess opens, threads internally of the nipple'for attachment of a drill shank therewith, diametrically opposed tangentially arranged outer cutting blades on sa1d stock and extended beyond the outer face lon 'tudinally thereof for a major portion 0 its length, radially disposed outwardly extending follower b ades on the stock at substantia ly right angles to the first named blades and havin beveled shear edges, said first. named blades having beveled shear edges, beveled reversely angled edged tips formed on the first named blades and protruded beyond the ends of the stock opposite the nipple, the second named blades being terminated inwardly with respect to the tips and having their outer surfaces rounded and tapering in the direction of the tips, a pair of shear blades located on the stock midwa between the first named blades and termmating flush with the outer face of said stock and dis osed at -a tangent to the axis thereof,and a pilot blade centrally on the outer end of the stock and having double beveled edges, one beveled edge of the latter being offset in parallel relation to the other, the stock having water passages leading from the recess there- I in to points inwardly with respect to the first and second named blades and opening through the outer end of the stock, certain of the passages being of larger extent than the remaining passages and disposed at a pitch to direct water et to the points and cutt' edges of said blades.

Y testimony whereof I aflix my signature.

FRED CLARK. 

